Lamp focusing



Feb. 7, 1928. 1,658,552

H. c. FOSTER LAMP FOCUSING Filed Jan. 29. 1925 INVENTOR: HABQY c.FOSTEQ,

Zm ATTORNEYS.

Patented 7, 1928.

UNITED STATES PATENT .OFFltllfi.

HARRY o. FOSTER, on oonivnnsvrnnn, INDIANA, ASSIGNOR, BY Dinner nn MESNEASSIGNMENTS, on one-near TO INDIANA LAMP CURPORATIO'N, or GQNNERS-VILLE, INDIANA, a oonronatrlolv ornnnnwenn. AND one-ants '20 GENERALMorons oonronn rron, or nnrnorr, MICHIGAN, a CORPORATION or DELAWARE.

LAMP FOCUSING.

Application filed January 29, 1925. Serial No. 5,532.

This invention relates to lamp tocusipg and is herein shown as embodiedin a IO- cusing device for the lan'ip otan automobile headlight.

An object of the invention 1s to prov de a simpl and inexpensive devicefor focusing a lamp filament or to restore a sagging or crooked filamentto proper position relative 1y to the reflector. Ano or object is toprovide eiiective means for transversely adjusting a lamp bulb,particularly a two-filament bulb which requires adjustment up or down toget maximum efliciency for a distant beam or for illuminating the roaddirectly in front of the car. 1

To these ends and. also to improve generally upon devices of thecharacter indicated my invention consists in the various mattershereinafter described and claimed.

Referring to the drawing Figure 1 is a side view of an automobileheadlight partly in vertical section.

Figure 2 is a vertical central section of a modified form of theinvention and Figure 3 is a perspective view of the socket.

In the drawings, the numeral 10 indicates a parabolic reflector enclosedin a casing 12. The reflector has a central opening where the metal isbent into a rounded bead Ll closely surrounding a lamp socket 16 and onwhich the socket can tilt, or slide in the direction of its axis. A lampbulb 20, having two filaments 22 and 24:, is detachably secured in thesocket 16, one filament preferably being above the reflector axis andthe other bolow it. Lead wires 26 and 28 connect the bulb with a sourceof lighting current.

Fixed to the end of the socket 16, or mtegral with it, is a plate orcross bar 30 having its ends 32 bent forwardly. The plate is also bentnear its ends to form two cross grooves or cavities 84 in which the tapered ends of nuts 36 are adapted to rock. Each nut is threaded on a bolt38 extending through openings in the plate 30 at opposite sides of theaxisof the socket The bolts also pass loosely through openings in thecasing 12 and their heads are accessible outside the casing. A coilspring 10 is coiled about each bolt and interposed between the casingand a washer 42 abutting against the plate 30. The springs hold theplate 30 against the nuts which are held from turning bytheir engagementwith said plate.

Turning both bolts equally eilects alon gitudinal shitting or sliding ofthe socket 16 through the opening in the reflector. Turning one bolt, orturning one more than the other, eiiects a tilting of the plate 30 and aconsequent tilting of the socket. about the bead let as a fulcrum. Thisthrows the lamp filaments up or down relatively tothe focus of thereflector. The tilting of the plate 30 also raises or lowers slightlythe free ends oi? the bolts and the plate 30 rocks on the tapered nuts.

In Figure 2, the lamp bulb 14: has one lilament at the focus and thesocket 4.6 and plate 48 are integrally formed from a piece of sheetmetal. The metal is stamped out and bent to form opposite flanges 50which embrace and hold square nuts 52. The plate 18 also has openings 54loosely traversed by bolts 56 the heads of which are accessible outsidethe casing 58 indicates a key on the socket which engages a slot in thereflector to keep the socket from turning.

The operation of theform of the device shown in Figures 2 and 3 issubstantially the same as that of the previous form. If both bolts 56are rotated in equal amount the socket 4:6 is adjusted axially. If onebolt is adjusted and not the other the socket is tilted either up ordown. The loose engagement of the bolts 56 in the openings 54: permitsof the latter adjustment.

Although the invention has been described by reference to a specificconstruction, it should be understood that it is not necessarily limitedto the construction selected for illustrative purposes.

I claim:

1. In a device oi the character described, a reflector having a centralopening, a socket slidable longitudinally through the opening andadapted to tilt on the rim of the opening, a lamp in the socket, a plateextending crosswise of the socket and connected there to, and bolts atopposite sides of the socket and having their heads fixed-againstlongitudinal movement relatively to the reflector, said bolts having arockable threaded connection with the plate for sliding the socketlongitudinally and tilting it transversely to focus the lamp.

2. In awdevice'of the character described, a reflectorhaving acentrelopening a socket slidable longitudinally through theuopening and adaptedtotilt on tllG-Illll of the opening, a lamp in the socket a plateextending crosswise of the-socket and connected thereto, taperednutshaving a rocking engagement With the plate and bolts having their headsfixed against longitudinal movement relatively to the reflector andthreaded in said nuts for sliding the socket "lcngitudh .nally andtilting it transversely to focus the in said nuts, said bolts havingtheir heads fixed against longitudinal movement relatively to thereflector and being independently. operable to slide the socketlongitudinally and tilt it transversely.

4. In a device of the character described, a reflector having a centralopening, a Socket slidable longitudinally through the opening andadapted to tilton the rim of the opening, a lamp in the socket, a plateextending crosewieewot theeocket and connected thereto, said platehaving grooves at opposite sides of the socket; nuts haying ro'ckableprojections in Said grooves, a caring, bolts passing loosely throughsaid plate and said casing and threaded in said nuts,rsaid bolts beingindependently operable to slide the Pocket longitudinally and tilt ittransversely; and springs interposed between-seid-casing and said plate.l

In testimony whereof I :ifiix my signathre.

HARRY G. FOSTER;

